The present invention relates to a refrigerator, a temperature controlling apparatus therefor and a method thereof, and more particularly, to a temperature controlling apparatus and method for use in a refrigerator which adopts a genetic algorithm (GA) fuzzy inference technique for achieving rapid and uniform distribution of a set temperature in the refrigerator.
As shown in FIG. 1, a refrigerator generally has a main body 4 of a thermal insulating structure including a freezer compartment 2 and a refrigeration compartment 3, with the compartments being separated by a partition 1 and provided with respective doors 6 and 7. Here, main body 4 comprises a cabinet 4a as the refrigerator's frame, a liner 4b formed on the interior of cabinet 4a, and foam material 4c filling the space between the cabinet and liner.
A compressor 11a is installed in a machine compartment 11 below refrigeration compartment 3; a condensing unit and pressure reducer (not shown) are installed on main body 4 or in machine compartment 11; and an evaporator 12 is installed behind the rear wall of freezer compartment 2. By coupling these elements together via refrigerant pipes, an air-cooling circulation cycle is performed. Also, a cooling fan 13 for forcibly blasting cool air generated at evaporator 12 into freezer and refrigeration compartments 2 and 3 is installed above evaporator 12. A fan guide 14 for guiding the supply of the cool air is situated in front of cooling fan 13. A cool air duct 15a is provided behind the rear wall of refrigeration compartment 3. A cool air adjusting damper 19 controls the amount of cool air supplied to refrigeration compartment 3. Shelves 8 for holding foodstuffs are spaced evenly inside refrigeration compartment 3.
A discharging-per-partition type is generally adapted as a method of supplying cool air to a refrigeration compartment in a conventional refrigerator. As shown in FIG. 2, cool air discharging apertures 16a are vertically arrayed in cool air duct 15a at the rear wall of refrigeration compartment 3 and correspond to the position of each of shelves 8. Thus, cool air is discharged into every area partitioned by shelves 8.
However, in a refrigerator of such a discharging-per-partition type, since the cool air is simply discharged, straight in front of cool air discharging aperture 16a, uniform cooling cannot be achieved due to the severe temperature distribution within the compartment.
To overcome the above problem, a refrigerator of a three-dimensional cooling type has recently been proposed. As shown in FIG. 3, the three-dimensional cooling type is featured in that cool air is discharged not only from cool air discharging apertures 16a formed on the rear wall but also from apertures 16b formed on both side walls.
However, though the cool air is discharged from the three sides of the above-described refrigerator, the cool air is simply discharged toward the compartment's interior and not dispersed, so that there is a limit of uniformly maintaining the temperature distribution between those portions of the refrigerator's interior which directly juxtapose the cool air discharging apertures and those which do not. Also, since the direction and amount of the discharged cool air are not controlled, particular portions of the interior cannot be cooled as required. That is, when a portion of the interior is at a relatively high temperature due the placement of warm or uncooled foodstuff or when cool air circulation is impeded by such placement, the maintenance of uniform compartment temperature, for example, by an intensified cooling action, is rendered impossible.
These problems become more critical when large-capacity refrigerators are considered. To rapidly and uniformly control the temperature distribution in the interior of such a refrigerator, a temperature controlling apparatus of fuzzy inference is generally employed, as shown in FIG. 4. The temperature of a refrigeration compartment, detected by an internal temperature sensor 104, changes according to unspecified varying factors such as external temperature detected by an external temperature sensor 101, door opening frequency detected by a door opening frequency counter 102, and a temperature variation rate calculated by a temperature-variation-rate calculator 103 according to the external temperature and the door opening frequency. Here, the temperature is controlled by using electromotive damper 105, compressor 106, and a fan motor 107. In doing so, fuzzy inference is applied by a fuzzy controlling apparatus 100 so that the temperature distribution is made rapidly and uniformly by supplying cool air while considering the above temperature variation factors, according to the compensation for external temperature and the status of stored foodstuffs.
However, since-only the fuzzy rule for analyzing the inputs according to unspecified temperature variation factors is adopted for the temperature controlling apparatus and method in such a refrigerator, the external temperature cannot be compensated for and the internal temperature control is unsatisfactory. That is, the cool air cannot be concentrated toward warm foodstuff due to the simple cool air discharging type or be properly supplied for compensating for temperature differences between each partitioned area, due to the higher temperature of the stored foodstuff or frequent door opening.